The Perfect Playlist: How Your iPod Can Help You Run Faster and Harder

Sometimes you need an extra push to hit the pavement or treadmill — or to make it through that last grueling mile of training — and the key may simply be loading right songs on your iPod, according to Dr. Costas Karageorghis, author of Inside Sport Psychology and a leading expert on the psychophysical and ergogenic effects of music at Brunel University, in London.

Music has specific motivational qualities that can make you work harder and faster, even when you feel spent. “Music has the propensity to elevate positive aspects of mood such as vigor and excitement, and reduces negative aspects such as tension and fatigue,” says Karageorghis, who has created custom workout soundtracks for several U.S. athletes competing in the London Olympics. “It reduces perceived effort, and training to a musical beat can enhance endurance.”

Whether you’re a casual runner or training for a distance event (if the latter, first check out our tips on training from last week), the right playlist can optimize your performance. Here are Karageorghis’ guidelines for putting together a runner’s mix that will get you across the finish line:

Select tracks with energizing beats
Synchronizing your strides with an upbeat song can subconsciously increase your effort during a workout. In a 2009 study, Karageorghis and his colleagues found that matching training with music significantly boosted exercise efficiency and endurance. For the study, the researchers compared 30 participants working out on a treadmill — some listened to high-energy rock and pop tunes and some did not. Compared with those who worked out in silence, those who synchronized their pace to the songs’ tempo improved their endurance by 15%.

Jamming to rhythmic songs also lowers your perceived effort, making you think you’re not working as hard as you really are. Upbeat music increases activity in a part of the brain called the ascending reticular activating system, which “psyches” you up when you’re running.

“The optimal tempo range is 120 to 140 beats per minute,” says Karageorghis. “Our research shows this yields the best psychological outcomes.”

By looking up the beats per minute (bpm) of your go-to songs, you can also find the tempo that matches the heart rate you want to achieve during your workout. For example, if you want your heart rate to get to 130 bpm, choose a song whose tempo progressively increases to that beat, Karageorghis says.

Stick with what you know
A song’s cultural impact is a key factor in what makes it motivational. “There’s a strong relationship between exposure to a song and you liking it,” says Karageorghis. We tend to favor songs the more often we hear them, so pick a song that’s already in your music library.

Adding songs you associate with moments of perseverance, either from movies or your personal life, can also give you an extra edge. The “Chariots of Fire [theme song] has been used extensively at the London Olympic games,” says Karageorghis. “We’ve made an association with this song and characters doing heroic feats. When you hear it, it conjures images and thoughts of overcoming adversity and striving towards a goal. So you’re conditioned to feel stimulated, inspired and motivated.”

One of TIME’s own staffers, photo editor Liz Ronk, who is training for a half-marathon in October, says this strategy has already worked for her: “Sometimes I hear songs that are played at races that I would normally never listen to, and I’ll download them specifically for my runs just because the song will remind me of that energy.”

Don’t forget to hit shuffle
If you’ve had your playlist on repeat for the last two weeks, you may be desensitized to the songs’ motivational qualities. “This is why radio stations promote songs by playing them repeatedly, but then play it less and less, so listeners don’t develop a negative response to it,” says Karageorghis. “Change your playlist at least every couple of weeks so you don’t listen to the same track over and over.”

Try digitally altering your music to boost motivation
To create playlists for professional athletes, includingGreat Britain‘s track and field captain, Dai Greene, Karageorghis films them working out at different intensities in order to identify tracks from their music libraries that fit their workouts. Then he tweaks the music to get them working ven harder. “Often I digitally adjust tracks to give a little push of one or two beats per minute,” says Karageorghis. “Differences in tempo of up to four beats per minute are indiscernible to non-musicians. You can easily manipulate your favorite tracks slightly. It’s a particularly good ploy if you want to give yourself a little jolt or get out of a training slump.”

Be choosy about lyrics
“Lyrics can be extremely important, particularly if they carry meaning for the athlete,” says Karageorghis. “You will notice a lot of athletes like your own Michael Phelps use music as an integral part of their pre-event routine. He’s famed for his rap-centric playlist. In Beijing, he listened to the song “I’m Me” by Lil’ Wayne which has strong affirming lyrics as well as being acoustically stimulative.”

Find songs with inspiring lyrics that convey what you want to achieve, like “Pump It” by Black Eyed Peas or “Lose Yourself” by Eminem.

If you’re still unsure where to start, below are sample playlists from Karageorghis and from our three TIME staffers who are training for half-marathons in October (stay tuned for ongoing updates about the training this summer):

Dr. Costas Karageorghis:

“Eye Of The Tiger” (109 BPM), Surivior

“Don’t Stop Me Now” (154 BPM), Queen

“Beat It” (139 BPM), Michael Jackson

“I Like To Move It” (123 BPM), Reel 2 Real feat. The Mad Stuntman

“Push It” (130 BPM), Salt-N-Pepa

Bryan Walsh, TIME International Senior Editor and Healthland contributor: